The rising cost of petroleum based fuels is generating increased demand for hybrid electric and internal combustion engined vehicles and pure electric vehicles (EVs) which in turn will create a need for kinetic energy, commonly termed braking energy, recovery and regeneration systems. Such regeneration systems convert a portion of a vehicle's kinetic energy normally dissipated as heat during braking into energy storable for future use. The recovered energy may be generated and stored pneumatically, hydraulically or in a flywheel, but most commonly it is generated as electricity and stored in batteries or supercapacitors.
The primary electric motor-generator of a hybrid or EV regenerates only a portion of the kinetic energy normally dissipated as heat during braking; auxiliary generators may be useful to supplement and maintain the battery or supercapacitor charge to increase the vehicle's useful driving range.
U.S. Pat. Nos. 7,255,187, 7,115,057, 6,935,451, 6,484,834, 6,208,036, 6,184,603, 5,947,855 and 5,562,565 are among numerous patents that describe transmission or final drive mechanisms in combination with electric motor-generators. None, however, incorporate pancake-type electric motor-generators orienting their rotor shafts vertically and/or perpendicular to the transmission output shaft, to engage with the final drive gears, or combine or integrate the motor-generator stator housing with the final drive housing.
The current invention is suitable for use as both a primary and a supplementary energy regeneration and reuse mechanism as its integrated design, location in the vehicle and pancake-type electric motor-generator lends itself to compact, space efficient sizing, low weight and efficient power and torque generation.
In addition, the kinetic energy regeneration mechanism can provide full-time or as-needed all-wheel-drive functionality to front-wheel-drive and rear-wheel-drive vehicles; for example, a front-wheel-drive vehicle would have such a mechanism to drive the rear wheels, while rear-wheel-drive vehicles would have the mechanism to drive the front wheels.
Current original equipment hybrid vehicles typically integrate their electric drive into the transmission and therefore such technology is unsuitable for retrofitting existing internal combustion drive vehicles. The existing fleet of internal combustion only vehicles will take decades to be replaced by hybrid vehicles.